Head jolting/jerking (Budgie) (I need help!)

Ever since we got our (currently) 4 month old female budgie Nua, she has always been doing head jerks while screaming. She is bobbing her head like this:
(But in a snappier fashion while doing short squawks/screams)
She doesn't do this often, but she does this usually when she's upset, or wants our attention. I don't know if this means she is just attention hungry, and we're feeding into that type of negative behaviour, or something else could be going on here. If I catch her doing it again, I'll make sure to filming it.